Related stories

Cortana, currently in beta (on an opt-in basis), is slated to be a major component in Microsoft's future operating systems for Windows Phone, Windows, and Xbox One.

It will eventually roll out to all Windows Phone 8.1 users worldwide in late 2014 and early 2015.

Note that CNET and other reviews have found Cortana "frustrating" in some respects due to bugs in the beta software, though they are expected to be fixed by the time it arrives on Windows Phone later this year.